(a) Field of the Invention
The present invention relates to a computerized exercise apparatus generally used for exercise, physical therapy, or rehabilitation having improved features. More particularly, the computerized exercise apparatus permits concentric and eccentric isokinetic exercise by a user where apparatus calibration is accurately determined before exercise to compensate for the user selected force application device, the push assembly means, if used, and environmental factors; where hydraulic flow can be accurately controlled by use of an alternating current dither circuit; where multiple user force application devices, a push assembly means, and a detachably connectable operator support are available for a myriad of exercises; and where the instantaneous forces measured during user exercise are displayed to the user in such a novel way so as to motivate the user to maximize their exercise efforts and thereby obtain increased personal benefit.
(b) Description of the Prior Art
The world of exercise equipment has grown from the days of bar bells and free weights. There are exercise machines having a user selectable weight and a system of levers, pulleys, chains, and other hardware such that a user can lift and lower the selected weight for the exercise the machine is designed to accomplish. These machines are of the type known under the trademarks "UNIVERSAL" and "NAUTILUS". All of these have the disadvantage that the same weight is used for both lifting and lowering and for each repetition of the exercise, unless the user interrupts his routine to change the weight amount.
Exercise equipment using an adjustable hydraulic piston and cylinder for variable user force application is taught in European Patent Application 0,135,346 to Wu. Wilson U.S. Pat. No. 4,063,726, teaches an electronically controlled exercising system which proportions the exercise resistance in the two directions of piston movement using a variable speed pump motor and a series of open or closed valves. Useldinger et al U.S. Pat. No. 4,307,608, teaches using the output of a load cell to determine peak force applied to the load cell under tension or compression and displaying this peak force to the user while the user is exercising.
Other devices which couple an exercise apparatus to a computer to allow for a programmed or selected exercise routine and to display some results of the exercise are taught. Sweeney Jr. U.S. Pat. No. 4,358,105, teaches an exercise cycle which is programmable to simulate cycling over a level or hilly path and displays variables such as hill profile, calories, and time of exercise through a series of light displays. Voris U.S. Pat. No. 4,765,613, teaches a varying resistance lifting mechanism which has a microprocessor which controls the resistance and calculates the user performance and displays this performance to the user.
Kolomayets et al U.S. Pat. No. 4,714,244, teaches a rowing machine having a video display which displays user instructions and the user's performance in relation to a "PACER" boat, along with landscapes and buoys. The "PACER" boat speed is varied by a microprocessor dependant upon the difficulty and duration of the exercise selected by the user. Nobuta U.S. Pat. No. 4,735,410, also teaches a rowing machine having a cathode ray tube display which allows a user to simulate rowing against various currents and winds and in waters having shorelines and obstacles.
Finally, Miller U.S. Pat. No. 4,919,418, teaches a computerized drive mechanism for exercise, physical therapy and rehabilitation which provides for isokinetic exercise reciprocating between the concentric and compulsory isokinetic eccentric modes. Improvements to the mechanisms taught in the Miller patent are the focus of this patent.